Ha, J.
Jeong, C.
Han, K.-D.
Lim, Y.
Kim, M.K.
Kwon, H.-S.
Song, K.-H.
Kang, M.I.
Baek, K.-H. http://orcid.org/0000-0002-4097-1077
Article History
Received: 3 February 2021
Accepted: 11 June 2021
First Online: 31 July 2021
Declarations
:
: The study was approved by the Institutional Review Board of the Catholic Medical Center (No. KC20ZISI0291). The need for informed consent was waived by the review board because all data provided by the NHIS to researchers were deidentified.
: The authors declare no competing interests.